This trip was - if I remember it correctly - on the last week of my stay. It's not a big trip or anything like that, you can literally decide the day you want to go that you want to go there, but it's usually the same with every territory you can get with a Lisbon transport card. The tricky part is getting there. While google maps suggests to take two to three trains/metros/buses/whatever, you can literally hop on a bus at Campo Grande and it will take you right there. The bus operates every hour and it will take you to a bu stop that's no where near to the beach, but do not worry because around thirty minutes of walking never killed anybody. It was quite enjoyable to have a walk in Ericeira, since it was a break from the tiled Lisbon look and it was somewhat refreshing to look at some white building without dealing with the Algarve heat.
Oh I forgot to mention. When me and my roommate headed towards Ericeira, I was in kind of a bad mood, I clearly remember that but I don't seem to recall its reason, and I thought some rays and the coast would cheer me up. So I thought. Apparently it was a sike situation, cause even if Lisbon was sunny and hot as one expects it to be, Ericeira is just a pure rebel and was not having it. Honestly, I was not prepared for the level of cloudiness and the audacity to be this cloudy in the summery Portugal. It's not even that far from Lisbon for it to make sense!
Anyway, when we got out the bus, we noticed that it's not that big of a deal, because at least it's not that cold as it appeared to be from the inside. I am even going to say that it got unbearably hot on the beach. We had some laugh at the people "tanning", but that was a sike situation as well, considering the shade of red we got after falling asleep in the sand without any protection from the sun. You can observe in the pictures how diffused the light actually is, some may say it's the easiest to get a sunburn in. Long story short, we are dumb in some terms. Also, conclusion: WEAR YOUR SUNSCREEN KIDS!
Ericeira is a lovely city (or town?). It has everything from a gorgeous coastline, to aesthetically pleasing fisherman facilities and to small commercial streets to please the tourists with fancy and hipster cafes and restaurants. In conclusion, it's purely lovely, as hopefully you can see it from the photos. I am truly confident that I will revisit Ericeira for quite a few times once I return Portugal for the next semester.
Oh by the way, it's an excellent place for surfing and I heard that its surf school is very good for starters and for some more advanced people as well.